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Your compression is just ABOUT right for 11:1. Depends on your altitude above sea level.
Do the math: Sea level atmosphere is 14.7 psia. As a first approximation, assume that the air does not heat as it is compressed because the heat is absorbed by all the cool metal. If that were true, then compression would be a straight multiple of the compression ratio (minus 1).
Since your frame of reference, or 'zero' point is a background of 14.7 psia (absolute), if you had a 2:1 compression, you would read 14.7 psig (guage). At 3:1 you would read 29.4 psig, and so on up to 11:1 where you would read 147 psig.
However, somewhere around 6:1 to 8:1, you start to generate enough heat of compression to be a factor in your measured pressure. Therefore, the actual measured pressure will be higher. If I knew your altitude, I suppose I could dig out my old thermodynamics textbook and figure out your theoretical compression pressure.
If you are a couple thousand feet above sea level or more, your compression is probably fine.
If you are not, the first thing I would suspect is the guage. Is it accurate?
The second thing I would suspect is that if you modified the engine to get higher compression, you probably put in a different cam. If the cam duration is such that the intake valve stays open into the compression stroke, you will loose compression back through the intake valve at cranking speed (but not at high RPM). That is one of the reasons that cars with long-duration cams have 'lumpy' idles.
The third and least likely possibilty is a leak past rings or valves. Highly unlikely with compressions all within 2% of each other. You can check for compression ring leakage by squirting oil into the cylinder and running the test on each cylinder a second time. I'm pretty sure you won't find a problem there.
Good luck.
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